The combined delta of the Ganges and Brahmaputra Rivers is the largest in the world. This true-color image from the <a href="http://modarch.gsfc.nasa.gov/">Moderate-resolution Imaging Spectroradiometer</a> (MODIS) shows both the delta and sediment flowing into the Bay of Bengal. Fed by monsoon rains and Himalayan snowmelt, the rivers often flood. These floods often cause catastrophic damage, but also enrich the soil.Launched in December 1999, MODIS flies aboard NASA's <a href="http://terra.nasa.gov/"> Terra</a> spacecraft. Sensor: Terra/MODIS.